Can someone please help me with this specific gravity question?

[whatwhy]

An object with 15 g mass is immersed in benzene and suffers an apparent loss of 5 grams. What is the approximate specific gravity of the object? (Specific gravity of benzene is 0.7)

Answer is 2.1

I got it right, but just dont understand it. I googled it and someone else had posted this a while ago but the answers didnt make sense. Thanks

---

Members don't see this ad.

 

[jetsfan1234]

Specific gravity = (density of substance)/(density of water). Density of water is = 1 as a reference point.

The submerged object displaces it's own volume of benzene. The weight of benzene displaced = 5 grams (remember the buoyant force = weight of fluid displaced, per archimedes). But the weight of the object itself is 15 grams. Therefore, the object is 3x as dense as the benzene. 0.7 x 3 = 2.1